Methods of sorting waste

ABSTRACT

A system for disposing of medical waste is generally configured to sort waste items into a plurality of disposable containers according to applicable rules and regulations governing the handling and/or disposal of such items. In some embodiments, a system comprises sorting stations, each of which houses a number of disposable containers. Each station can identify an item of waste, determine the most appropriate container for the item, and facilitate disposal of the item in the appropriate container.

RELATED APPLICATIONS

This is a continuation of U.S. patent application Ser. No. ______,(Attorney Docket No. VESMED.001A), titled SYSTEM AND METHOD FOR SORTINGMEDICAL WASTE FOR DISPOSAL, and filed on Sep. 20, 2004, which claims thebenefit of U.S. Provisional Patent Applications Ser. No. 60/504,170filed Sep. 19, 2003 and Ser. No. 60/589,118, filed Jul. 19, 2004, all ofwhich are incorporated by reference herein in their entireties.

BACKGROUND

1. Field of the Invention

The invention relates in general to the field of waste disposal systems,and in particular to a system for sorting medical waste for disposal.

2. Description of the Related Art

The Environmental Protection Agency (EPA) enforces the ResourceConservation & Recovery Act (RCRA) which was enacted in 1976 in order tocontrol the disposal of harmful or hazardous waste materials. There arecurrently over 100,000 drugs commercially available in the UnitedStates, of which about 14,000 are considered hazardous by RCRArequirements. A typical medium size hospital utilizes thousands ofdifferent drugs in a year of which hundreds are considered hazardous.The EPA is increasingly enforcing hospitals' compliance with the RCRArequirements because it has been shown in several studies that the 72million pounds of pharmaceutical waste generated each year by hospitalsis contributing to the pollution of groundwater and endocrine systemdamage in humans and other species. In addition, many organizationsincluding Hospital for a Healthy Environment (H2E) and Joint Council forAccreditation of Healthcare Organizations (JCAHO) are pressing hospitalsto be more environmentally friendly. In view of these changes, hospitalsare increasing efforts to audit their own compliance with the laws. As aresult, these hospitals are becoming more aware of the difficulty ofsorting the numerous pharmaceutical waste streams that the EPA,Department of Transportation (DOT), Drug Enforcement Administration(DEA), and some states require.

More than 3.2 million tons of medical waste is generated by hospitals,medical clinics and pharmaceutical manufacturers each year. Half of thiswaste is considered infectious. Most of the infectious waste was treatedin over 2400 incinerators throughout the country, until 1998 when theEPA began to enforce tough environmental emission laws that have reducedthe number of incinerators to just over a hundred nationwide. Now muchof the infectious waste is hauled to these remaining incinerators, oftena substantial distance, or is treated by alternative technologies suchas autoclaves and chemical processors. There is very little choice forhospitals because of the upfront cost and large footprint of theprocessing equipment. Although many companies have offered differentkinds of equipment, the prices vary from a few hundred thousand dollarsfor smaller units to a few million for large units. Because of the longcycling times to decontaminate the waste, the equipment typically isvery large in order to provide acceptable throughput. There are alsoseveral companies that provide a service to hospitals by utilizingchemical processors mounted on trucks. They go to a facility anddecontaminate the infectious waste, allowing the treated waste to behauled to a local landfill. There are concerns that this technology maynot completely treat the waste in all circumstances and the chemicalresidue left after processing may remain an ecological issue.

Increasingly, hospitals are required to comply with the recent andprojected enforcement of federal and state hazardous pharmaceuticalwaste regulations. Currently, clinicians must manually sortpharmaceutical waste streams into different colored containers forproper disposal of the separate waste streams. It is often not clear toa clinician which pharmaceuticals or waste materials are hazardoussimply by looking at the container. Such confusion may lead toclinicians throwing hazardous drugs in non-hazardous containers such assharps containers, infectious waste bags, non-hazardous pharmaceuticalcontainers or simply down the drain.

SUMMARY OF THE INVENTION

There remains a need for a system for allowing clinicians to more easilysort medical waste items for appropriate disposal. There also remains aneed for an automated system of waste disposal that encourages andfacilitates hospital compliance with the relevant federal and stateregulations.

Several embodiments of the present application describe systems anddevices to sort and process infectious and pharmaceutical waste streams.Embodiments of a medical waste sorting system advantageously provide alabor savings for doctors, nurses and other clinicians by taking thebulk of the decision making associated with sorting medical waste awayfrom the clinician. In one embodiment, a medical waste sorting system isprovided, which will help clinicians conveniently comply with the recentand projected enforcement of federal and state hazardous waste laws. Insome embodiments, the system can be configured to scan a bar code, RFIDtag, or other system for identifying a spent drug. The spent drug canthen be classified into an appropriate waste category, and a door can beautomatically opened to provide access to a unique waste container forconvenient disposal of the drug in compliance with applicableregulations.

According to another embodiment, a system is provided which will renderinfectious hospital or laboratory waste non-infectious. This embodimentwill provide an economical service to a hospital by utilizing aself-contained truck-mounted version. Alternatively, a stand aloneversion can be made available for hospital purchase.

In another embodiment, a system for treating hazardous medical wasteitems in order to render them non-hazardous is provided.

In addition to the need for medical and pharmaceutical waste sorting,there exists a need to improve areas of water quality analysis andworkplace safety. These areas include sampling water quality throughoutthe hospital to pinpoint inappropriate dumping of hazardous materialsdown the drain and improved programs that reduce hospital workerexposure to hazardous materials in the workplace.

In one embodiment, a system for sorting waste is provided. The system ofthis embodiment comprises a plurality of containers associated with aplurality of waste categories. A waste item identification device isconfigured to determine a qualitative parameter of an item of medicalwaste. A database is provided with medical waste item classificationinformation. A control system is programmed to compare the qualitativeparameter of the waste item to information contained in the database inorder to assign the item to a medical waste category. The system alsoincludes a sorting mechanism configured to place the item into one ofthe containers based on the medical waste category.

In another embodiment, a system for sorting waste comprises a waste itemidentification means for identifying a qualitative parameter of an itemof medical waste, and a database means for classifying medical wasteitems into categories according to rules and regulations affecting thedisposal of medical waste items. The system also includes control meansfor comparing the qualitative parameter of the waste item to informationcontained in the database, and for assigning the item to a uniquemedical waste category. A sorting means is also provided for placing theitem into a container associated with the waste category.

In another embodiment, a system for determining the level of contentswithin a waste container is provided. The system of this embodimentcomprises a plurality of containers, each one being associated with atleast one of a plurality of a waste categories. Waste is placed in thecontainers based on a determination by a database that comprises medicalwaste classification information. At least one optical source ispositioned on one side of at least one of the containers, and at leastone optical detector is positioned on an opposite side of at least oneof the containers. A processor is configured to determine a level ofcontents of a container by analysis of the data received from theoptical detector.

Another embodiment of a system for determining the level of contentswithin a container comprises a means for containing waste itemscomprising a plurality of containers, and a means for producing anoptical signal on one side of at least one of the plurality ofcontainers. A means for receiving an optical signal is positioned on anopposite side of at least one of the containers, and means forprocessing signals from the respective means for producing and means forreceiving is configured to determine a level of contents within at leastone of the containers.

In another embodiment, a system comprises a container for storing sortedwaste and a sensor configured to measure a presence of waste within thecontainer without physically contacting the container. In anotherembodiment, a system comprises a means for storing sorted waste and ameans for determining a quantity of waste within the container.

In another embodiment, a disposable container for use in a medical wastesystem comprises a plurality of walls defining an internal space and anopening configured to provide access to the internal space. Anautomatically operable door is configured to selectively occlude andreveal the opening, and the door is configured to be operated by amachine in which the container is placed. A machine-readableidentification key is provided on at least a portion of the container.The machine-readable identification key bears a container type whichdefines a category of waste to be placed in the container.

In another embodiment, a disposable container for use in a medical wastesystem comprises a plurality of walls defining an internal space and anopening configured to provide access to the internal space. A flangeextends from a portion of the container and comprises a pattern of holesconfigured to indicate a container type. The container type defines atleast one category of waste to be placed in the container.

In another embodiment, a system comprises a plurality of disposablecontainers of different types. Each container type corresponds to acategory of medical waste, and each container comprises amachine-readable key configured to indicate the container's type to asorting machine. Each container also comprises an automatically-operablegate configured to selectively occlude and reveal an opening of thecontainer. The gate is further configured to be automatically locked.

In another embodiment, a container for use in a medical waste systemcomprises a means for defining an internal space, and an aperture meansfor providing access to the internal space. An openable means forselectively occluding and revealing the aperture means is operable by anautomated machine. A key means is also provided for indicating acontainer type to the machine.

In another embodiment, a disposable container for use in a medical wastesystem comprises a means for defining an internal space and a means forprovide access to the internal space. A flange means extends from aportion of the container and indicates a category of waste to be placedin the container.

In another embodiment, a method of using a disposable containercomprises receiving a disposable container in a sorting machine. Themethod is continued by reading an identification key on the container.The identification key defines a category of waste to be placed in thecontainer. The method is continued by directing a user to place aplurality of waste items in the container and alerting a user when thecontainer is full.

In another embodiment, a method of using a disposable containercomprises receiving a plurality of disposable containers in a sortingmachine, wherein each container corresponds to a waste category. Themethod further comprises reading an identification key on eachcontainer. The identification key defines a category of waste to beplaced in the container. The method further comprises determining awaste category to which an item of waste belongs, providing access to aselected one of the containers, and directing a user to place the wasteitem in the selected container.

In another embodiment, a method of using a disposable container forsorting and disposing of medical waste comprises placing a plurality ofcontainers in a sorting machine. Each container comprising an openingconfigured to provide access to an internal space. The method furthercomprises operating the machine to read an identification key from eachcontainer to determine a category of waste to be placed in eachcontainer and to automatically operate a door to selectively occlude andreveal the opening.

In another embodiment, a method of sorting medical waste comprises, inno particular order, receiving an identifier associated with waste to bedisposed of, and retrieving (based on the identifier) information from adatabase. The information is derived from applicable rules regardingdisposal of waste items. The method further comprises assigning thewaste to a disposal category based on the information retrieved from thedatabase, locating a container associated with the assigned disposalcategory, and facilitating disposal of the waste item into the containerassociated with the assigned disposal category.

In another embodiment, a method of sorting medical waste for disposalcomprises identifying a plurality of containers in a sorting station anddetermining a waste category associated with each container, identifyingan item of waste to be disposed of, and assigning the item to a wastecategory.

In another embodiment, a method of sorting medical waste comprisesidentifying a plurality of containers in a sorting station anddetermining at least one waste category associated with each container.The waste categories are ranked from least to most hazardous. The methodfurther comprises identifying an item of waste to be disposed of, andassigning the item to a first waste category. The method furthercomprises determining whether a container associated with the firstwaste category is present in the sorting station, and if one is notpresent, re-assigning the waste item to a second waste category that isranked more hazardous than the first waste category.

In another embodiment, a method of sorting medical waste items fordisposal comprises identifying a plurality of containers in a sortingstation and determining a waste category associated with each container.The waste categories are again ranked from least to most hazardous. Themethod further comprises identifying an item of waste to be disposed of,and assigning the item to a first waste category. The method furthercomprises determining whether a container associated with the firstwaste category is present in the sorting station, and if one is notpresent, directing a user to another sorting station which does have acontainer associated with the first waste category.

In another embodiment, a system for sorting medical waste itemscomprises a sorting station in electronic communication with aclassification database which lists a plurality of waste itemidentifiers distributed into a plurality of waste categories. Aplurality of containers are positioned in the sorting station. Eachcontainer is sized and configured to receive a plurality of medicalwaste items. A waste item identification device is configured to receivea waste item identifier from a waste item. A decision system isconfigured to classify the waste item into a waste category using thewaste item identifier and information contained in the classificationdatabase. Each of the containers is associated with one of the wastecategories, and the decision system is further configured to indicateinto which of the containers a waste item should be deposited based onthe waste category.

In another embodiment, a waste sorting and disposal system comprises asorting and disposal station comprising a waste item identificationdevice and a plurality of container compartments. The system also has adatabase which comprises medical waste item classification informationderived from rules and regulations affecting the disposal of medicalwaste items, and a plurality of containers positioned in the containercompartments. Each container comprises a machine-readable identificationkey and an automatically operable door formed integrally with thecontainer. The station is configured to read each identification keyupon placement of a container in a container compartment, and toselectively open and close the doors of each of the plurality ofcontainers.

In another embodiment, a system for sorting medical waste itemscomprises a sorting station in electronic communication with aclassification database which lists a plurality of waste itemidentifiers distributed into a plurality of waste categories. The wastecategories are ranked from least to most hazardous. A plurality ofcontainers are positioned in the sorting station, each container beingsized and configured to receive a plurality of medical waste items. Awaste item identification device is configured to receive a waste itemidentifier from a waste item, and a decision system is configured toassign the waste item to a waste category using the waste identifier andinformation contained in the classification database. Each of thecontainers is associated with at least one of the waste categories, andthe decision system is further configured to indicate into which of thecontainers a waste item should be deposited based on the waste category.The decision system is further configured to open a container associatedwith a highest hazardousness level if the station does not include acontainer associated with the assigned category.

In another embodiment, a system for sorting medical waste itemscomprises a plurality of sorting stations in electronic communicationwith one another via a central processing unit in a centralized network.The sorting stations and the central processing unit are oftenphysically separated from one another. A classification database, whichlists a plurality of waste item identifiers distributed into a pluralityof waste categories, resides in the central processing unit. Eachsorting station comprises a plurality of containers, and each containeris sized and configured to receive a plurality of medical waste items. Awaste item identification device is configured to receive a waste itemidentifier from a waste item, and a decision system is configured toclassify the waste item into a waste category using the waste identifierand information contained in the classification database. Each of thecontainers is associated with one of the waste categories, and thedecision system is further configured to indicate into which of thecontainers a waste item should be deposited.

In another embodiment, a system for sorting medical waste itemscomprises a plurality of sorting stations in electronic communicationwith one another in a de-centralized network. The sorting stations arephysically separated from one another, and a classification databaseresides on a data storage device in at least one of the stations. Thedatabase lists a plurality of waste item identifiers distributed into aplurality of waste categories. Each sorting station comprises aplurality of containers, and each container is sized and configured toreceive a plurality of medical waste items. Each container is designatedas a specific type which defines a group of items to be placed therein.A waste item identification device is configured to receive a waste itemidentifier from a waste item, and a decision system is configured toclassify a waste item into a waste category using the waste identifierand information contained in the classification database. The decisionsystem is further configured to indicate into which of the containers awaste item should be deposited.

In another embodiment, a method of sorting medical waste items comprisesjoining a plurality of physically separated sorting stations inelectronic communication with one another in a network. The methodfurther comprises joining each sorting station in electroniccommunication with a classification database which lists a plurality ofwaste item identifiers distributed into a plurality of waste categories.The method further comprises placing a plurality of containers in eachstation, each container being sized and configured to receive aplurality of medical waste items. The method further comprises providingeach station with a waste item identification device configured toreceive a waste item identifier from a waste item, and configuring adecision system in each station to classify waste items into wastecategories using the waste identifier and information contained in theclassification database.

In another embodiment, a waste system comprises a station comprising awaste identification device and a plurality of container compartments. Aplurality of containers are positioned in the container compartments,and each container comprises a machine-readable identification key. Thestation is configured to read each identification key upon placement ofa container in a container compartment.

In another embodiment, a waste system comprises a means for sortingwaste comprising a means for identifying waste and means for supportinga container. Each one of a plurality of means for containing wastecomprises a means for machine identification of the means for containingwaste. The means for sorting further comprises a means for reading eachmeans for machine identification upon placement of a means forcontaining in a means for supporting.

In another embodiment, a waste sorting and disposal system comprises asorting and disposal station comprising a waste identification deviceand a plurality of container compartments A plurality of containers arepositioned in the container compartments, each one comprising amachine-readable identification key which identifies a waste categorydefining characteristics of the waste to be placed in each container.The station is configured to read each identification key upon placementof a container in a container compartment, and the waste category ofeach container is independent of the container compartment in which eachcontainer is positioned.

In another embodiment, a sorting system for separating waste into aplurality of containers based on a classification of the waste item isprovided. The system comprises a plurality of containers, eachassociated with at least one of a plurality of a waste categories. Awaste detector is configured to identify waste presented to thedetector. A sorting mechanism is configured to place waste into one ofthe containers based on information received from the waste detector.The system also comprises a sensor configured to determine whether atleast one of the containers has waste therein.

In another embodiment, a sorting system for separating waste into aplurality of containers based on a classification of the waste isprovided. The system of this embodiment comprises a plurality ofcontainers, each associated with at least one of a plurality of a wastecategories. A database comprises waste classification informationderived from rules and regulations affecting the disposal of wasteitems. A waste detector is configured to identify waste presentedthereto, and a sorting mechanism is configured to place waste into oneof the containers based on information received from the waste detector.A sensor is configured to determine whether at least one of thecontainers has waste therein.

In another embodiment, a sorting system is provided for separating wasteinto a plurality of containers based on a classification of the waste.The system comprises a plurality of means for containing medical waste.Each of said means for containing medical waste is associated with atleast one of a plurality of a waste categories. A means for identifyingwaste is provided, as is a means for sorting waste into one of the meansfor containing using information received from the means for identifyingwaste. The system also comprises a means for determining whether atleast one of the containers has waste therein.

BRIEF DESCRIPTION OF DRAWINGS

FIG. 1 is a schematic illustration of one embodiment of medical wastesorting and disposal system including a plurality of interconnectedsorting and disposal stations in a centralized network;

FIG. 2 is a schematic illustration of one embodiment of medical wastesorting and disposal system implemented in a decentralized network;

FIG. 3 is a perspective illustration of an embodiment of a wall-mountedsorting and disposal station;

FIG. 4 is a perspective illustration of one embodiment of afloor-standing sorting and disposal station;

FIG. 5 is a front perspective view of one embodiment of a rolling cartsorting and disposal station;

FIG. 6 is a rear perspective view of one embodiment of a rolling cartsorting and disposal station;

FIG. 7 is a perspective view of one embodiment of a sorting and disposalstation incorporated into a rolling medications cart;

FIG. 8 is a rear perspective view of one embodiment of the cart of FIG.7;

FIG. 9 is an alternative embodiment of the cart of FIG. 7;

FIG. 10 is a partially exploded perspective view of one embodiment of asorting and disposal station comprising pivotable containers andsleeves;

FIG. 11 is a perspective view of one embodiment of a sorting anddisposal station in the form of a convertible rolling cart in a firstconfiguration;

FIG. 12 is a perspective view of one embodiment of the convertiblerolling cart in a second configuration;

FIG. 13 is a perspective view of one embodiment of a disposablecontainer and portions of an interface with a sorting and disposalstation;

FIG. 14 is a perspective view of an alternative embodiment of adisposable container and portions of an interface with a sorting anddisposal station;

FIG. 15 is a perspective view of an alternative embodiment of adisposable container;

FIG. 16 is a perspective view of an embodiment of a disposable containerand an alternative embodiment of portions of an interface with a sortingand disposal station;

FIG. 17 is a perspective view of an embodiment of a disposable containerand an alternative embodiment of portions of an interface with a sortingand disposal station;

FIG. 18 is a schematic side elevation view of an embodiment of a filllevel sensor;

FIG. 19 is a block diagram of one embodiment of a fill-level detectionsystem;

FIG. 20 is a an overview flow chart of one embodiment of a softwarealgorithm for measuring a fill level of a container;

FIG. 21 is a detailed flow chart of one embodiment of a method ofmeasuring a fill level of a container

FIG. 22 is a continuation of the flow chart of FIG. 5;

FIG. 22 a is an electronic schematic of one embodiment of an array oflight detectors

FIG. 23 is a block diagram of an alternative embodiment of a levelsensor system employing a video camera;

FIG. 23 a is an electronic schematic of one embodiment of an alternativeembodiment employing a video system;

FIG. 24 is a flow chart illustrating one embodiment of a sortingalgorithm for use by embodiments of a medical waste sorting and disposalsystem; and

FIG. 25 is a flow chart illustrating a container-checking subroutine foruse by embodiments of a medical waste sorting and disposal system.

DETAILED DESCRIPTION

Waste Sorting And Disposal System

Embodiments of devices and methods for sorting a plurality of medicalwastes will now be described with reference to the attached figures. Inseveral embodiments, the waste sorting and disposal system is automated.In some embodiments, a medical waste sorting system comprising aplurality of individual sorting and disposal stations connected to oneanother via a centralized or de-centralized network is provided.Alternatively, a medical waste sorting system can comprise one or morestand-alone sorting and disposal stations configured to operateindependently of any other device. Although some of the followingembodiments are described in the context of individual stand-alonestations, it should be recognized that such individual stations can beconnected in a networked system to provide additional functionality orto improve efficiency. Conversely, some embodiments are described belowin the context of networked systems, certain features and advantages ofwhich can be readily applied to individual stand-alone systems as willbe clear to the skilled artisan. The term “sorting” is a broad term andshall be given its ordinary meaning and generally refers to thedistribution of one or more waste items into one or more appropriatewaste receptacles. The term “disposing” is also a broad term and shallbe given its ordinary meaning and shall, in some embodiments, generallyrefer to the discarding or “throwing out” of one or more items of wasteinto an appropriate receptacle.

In one embodiment, a waste sorting and disposal station comprises asorting station or machine, which includes a series of containerpositions or compartments, each compartment being configured to receivea disposable container for collecting waste belonging to a particularcategory or classification. Some embodiments of a sorting stationcomprise a waste-identifying device, a processor configured to carry outa waste-sorting algorithm, and a waste-sorting mechanism.

In some embodiments, a sorting machine comprises one or more sensors fordetermining the presence of a container, a type of container, and/or avolume or weight of a container. In another embodiment, the sortingmachine includes one or more sensors (e.g., an optical sensor) todetermine which container the item was deposited into and/or a time atwhich an item is deposited. Additionally, a sorting machine/station caninclude any of a variety of computer peripherals, such as user inputdevices (e.g., touch screens, keyboards, pointer devices, etc.), displaydevices, sound-producing devices (e.g., speakers or buzzers), or anyother peripheral device.

In many embodiments, several container types are provided, each typebeing associated with a particular category or classification ofpharmaceutical waste. For example, in some embodiments, container typescan include sharps containers, chemotherapy agent containers, infectiouswaste containers, ignitable waste containers, hazardous P-list wastecontainers, hazardous U-list waste containers, toxic pharmaceuticalwaste containers, non-toxic pharmaceutical waste containers,chemotherapy sharps containers, corrosive waste containers, or reactivewaste containers. Additional container types can also be used asdesired. In one embodiment, the container types are pre-designated bythe container provider. In other embodiments, the container types areassigned by the hospital so that the hospital can individually customizeits waste sorting system. For example, some hospitals may desire todefine their own waste categories in order to comply with internalgoals, thus user-defined container types can also be provided.

In a preferred embodiment, a waste identifying mechanism is provided. Inseveral embodiments, the waste identifying mechanism is configured toidentify a particular item of waste. Identification is preferablyaccomplished prior to deposit into the appropriate container.Identification of the waste item can be accomplished by scanning abarcode, reading a label (e.g., using an optical scanner and OpticalCharacter Recognition software), reading a Radio Frequencyidentification (RFID) tag, chemical sensors, spectroscopic analyzers, orby measuring or evaluating any other qualitative parameter of the wasteitem presented for identification. Alternatively still, an item of wastecan be identified by user input of information such as a trade name, ageneric name, a chemical name, National Drug Code (NDC) or other dataassociated with a particular item of waste. For example, a user cansimply read a waste identifier from an item of medical waste and enterthe identifier into the system via a keyboard, touch screen or otheruser input device.

In one embodiment, once an item of waste is identified, the sortingalgorithm determines to which of a plurality of waste categories theitem belongs. The station then indicates to the user which container isassociated with that category. For example, in some embodiments thestation indicates a correct container by opening a door providing accessto the container. Alternatively, such an indication can be provided byilluminating a light or displaying a name or number of a container on adisplay device. In some embodiments, a waste sorting mechanism can carryout or instruct a user in delivery of the waste item to the appropriatedisposable container.

In some embodiments, the waste sorting mechanism comprises a pluralityof openings providing access to the plurality of containers. Forexample, each of the containers can be configured to interface with anautomatically operable door or other means to present the containeropening to the user. Some embodiments of such an interface are describedin further detail below. Alternatively, the sorting machine can beconfigured to provide access to an appropriate container in other ways,such as by moving a container relative to the machine in order topresent a container opening to a user. In further alternativeembodiments, the sorting mechanism can include a series of lights orother indicators configured to inform a user of the correct containerfor a particular item of waste. Alternatively still, the sortingmechanism can include an apparatus configured to receive an item ofwaste from a user and physically convey the item to the appropriatedisposable container.

In some embodiments, a single waste item may call for disposal inmultiple containers. For example, a syringe might contain a quantity ofa hazardous or controlled substance, which requires disposal in a firstcontainer. However, the syringe itself may require disposal in a second,separate container. In such embodiments, it is desirable for the systemto determine an appropriate sequence for the disposal of the separateparts of a single item. In the event that a waste item containsinformation (such as a barcode or label) sufficient to inform the systemof the need for a sequence of disposal steps, the system can determinethe optimum sequence, and can then inform the user of the appropriatesequence. The system may inform a user of the appropriate sequence bysequentially opening appropriate doors and/or by displaying instructionson a display screen. In one embodiment, a means can be provided todetermine whether an item of waste is empty or contains residual or bulkhazardous or non-hazardous contents.

Alternatively, it may be desirable for a user to determine the bestsequence for disposal, in which case, the user may enter informationinto the system requesting a particular sequence. Additionally, it mayalso be desirable for the system to include “shortcut keys” in order toprovide quick access to frequently-used containers, such as sharpscontainers. Such shortcut keys can be configured to quickly open aselected container.

In some embodiments, when a single waste item comprises a composite ofelements falling into different waste categories, such as a syringecontaining a controlled substance, which might, if disposed separately,be sorted into two different containers, the waste sorting system canindicate disposal of the composite waste item into the highest hazardlevel container. In this manner, when it is inefficient, ineffective oreven dangerous to separate the single composite waste item into itsindividual components, hospitals can still achieve compliance bydisposing of such hybrid or composite items into the most conservativehazard container. In some embodiments, the containers within a sortingstation can be ranked in order from “least” to “most” hazardous in orderto facilitate a determination of which container is the “mostconservative” hazard container in a given station. A determination ofwhether a particular container type (and corresponding waste category orcategories) is higher or lower on a hazardousness spectrum can bedetermined by a variety of suitable methods. In some cases, ahazardousness spectrum can be determined empirically, while in otherembodiments, the varying degrees of hazardousness may be determined bycomparing properties such as relative reactiveness, bioactivity, etc. ofelements of a particular category.

In some embodiments, when a waste item is unrecognized by theidentification means, the sorting system will indicate disposal to thehighest hazard waste container. The system will notify the disposer thatthe waste item was unrecognized. In another embodiment, the sortingsystem may also notify a database or database personnel that the wasteitem is unrecognized, thus facilitating a database upgrade to includethat waste item for future disposals.

In some embodiments of the invention, it may be advantageous todetermine the quantity of waste that has already been deposited into oneor more containers. In some embodiments, one or more sensors are used toquantitatively assess one or more parameters of the container and/orwaste. These quantitative sensors include, but are not limited to,sensors that detect the weight, volume, density, and/or fill level ofthe waste in the container.

In one embodiment, one or more fill sensors are provided. A fill levelsensor can be used to monitor a fill level of each of the disposablecontainers to determine when a particular container is full. Once acontainer is determined to be full, the sorting system can signal a userto replace the full container with a new empty container. Additionally,once a particular container is full, some embodiments of the system canbe configured to determine the weight or volume of waste material withinthe full container. The system can also be configured to print a labelto be affixed to the container. The label can include a variety ofinformation relating to the disposal of the waste items, the quantity,weight or volume of the items contained therein, a waste category nameor code, etc.

In some embodiments, quantitative sensors are not used. Instead, in oneembodiment, the quantity of waste is determined by direct visualizationof the waste in a container. Transparent or translucent containers areprovided to facilitate visualization in some embodiments. In severalembodiments, the containers are opaque, but provide a section or“view-strip” of translucent or transparent material to permitvisualization. In one embodiment, one or more sensors are provided inconjunction with means to directly visualize waste quantity. In oneembodiment, means for detecting a quantity of waste are not neededbecause the containers are replaced at regularly scheduled intervals, asdetermined by a waste transport company, a disposal company or hospitalstaff and independent of how much waste is in any given container.

In some embodiments, when a new container is placed in a sorting anddisposal station, the system can be configured to identify the newcontainer according to the type of waste the container it is permittedto hold. In some embodiments, a waste sorting and disposal station canbe configured to recognize containers in a static mode in which eachcontainer position within the station/machine is associated with aspecific container type. Upon insertion of a new container into thestation, the system can recognize the type of container and candetermine whether the new container is the correct type for the positionin which it was placed. Thus, a system of this type can insure that aconsistent arrangement of container types is maintained.

Alternatively, and more preferably, a sorting and disposal station isconfigured to recognize container types in a dynamic mode in which themachine is able to recognize and adapt to changing containerarrangements. Thus, according to this embodiment, each containerposition/compartment in a station will recognize and accept any newcontainer regardless of the container type, and the software will adapta sorting routine to account for the new configuration. In some cases,it may be desirable for a single station to have multiple containers ofa single type. For example, an oncology department may desire severalchemotherapy containers and no hazardous pharmaceutical containers,while an area of the hospital that does not use chemotherapeutic drugsmay want several sharps containers and no chemotherapy containers. Thisallows for substantial flexibility and customizability in system set up.In further embodiments, a sorting and disposal station can exhibitaspects of both static and dynamic systems, such as by allowing any typeof container in any container position, while requiring a minimum numberof containers of a particular type.

Network-Implemented System

In some embodiments, a waste sorting and disposal system can beconfigured on a hospital-wide level by providing a plurality ofcooperating sorting and disposal stations throughout the hospital. Thesystem can include a plurality of individual sorting and disposalstations in a variety of types, arrangements, sizes, functionalities,etc.

FIG. 1 illustrates an exemplary embodiment of a centralized wastesorting and disposal network. As shown, a centralized network 50 caninclude a main central unit 54 provided in electronic communication witha plurality of smaller “satellite” units 60 throughout a facility. Insuch a centralized network, the main unit 54 can include a servercontaining the classification database 56 and any other information tobe shared with the satellite units 60. As information is needed by asatellite unit 60, it can query the database via the network in order toobtain that information. Alternatively, or in addition, the main unit 54can be configured to push updates to the satellite units at regularintervals, or as new information becomes available. In some embodiments,the main unit 54 can also act as a central hub for variouscommunications, tracking, maintenance and other system functions.

FIG. 2 illustrates an embodiment of a de-centralized medical wastesorting and disposal system. The network 64 of FIG. 2 is substantiallydecentralized and comprises a plurality of sorting and disposal stations60 which can communicate with one another according to any suitablemethod. For example, in a decentralized network, each of the individualunits may locally store a copy of the classification database. In orderto keep the classification database updated, the individual units canshare information with one another according to any of a variety ofpeer-to-peer network protocols. The individual stations can also shareother information with one another as will be further described below.

In either case (centralized or decentralized network), the networkelements can be configured to communicate with one another via anysuitable wired and/or wireless network communication protocol. Manyhospitals already have existing wired and/or wireless networksconnecting computers and communications devices throughout the facility.Thus, in some embodiments, a networked medical waste sorting anddisposal system can be configured as an add-on to an existing network.Alternatively, a networked medical waste sorting and disposal system canbe configured as an independent network. Additionally, the main unit (ifpresent) and/or the satellite unit(s) can further be connected toexternal networks (e.g., the internet) via wireless or wired connectionsas desired.

In some embodiments, it may be desirable for one sorting and disposalstation to have access to information about one or all of the otherstations in the network. For instance, it may be desirable for any onestation to determine an arrangement of containers in one or more nearbystations. For example, if a clinician presents an item of waste to astation which does not presently have a container suitable for disposalof the presented item, that station can direct the clinician to thenearest station that does have an appropriate container installed. Infurther embodiments, a log of such re-directions can be kept in order toincrease efficiency by arranging the sorting and disposal stations toinclude the most frequently used containers for a given location.

Some embodiments of a waste sorting and disposal system are configuredto communicate information directly to a technician, maintenance person,clinician or other person. For example, the system can be configured toalert a maintenance person when a container is full by sending an alertsignal to a pager, cell phone, PDA, computer terminal, or any othersuitable device. The maintenance person can then remove the fullcontainer and replace it with an empty container (of the same or adifferent type).

Individual Sorting/Disposal Stations

A medical waste sorting and disposal station can take a variety of formsdepending on the specific needs of a given clinic, hospital, department,clinician, etc. For example, some embodiments of sorting and disposalstations 60 are illustrated in FIGS. 3-12. For example, a station can beprovided in a wall-mounted unit 60 a (e.g., see FIG. 3), in afloor-standing unit 60 b (FIG. 4), on a wheeled cart 60 c (FIGS. 5 and6), attached to a patient bed, attached to an IV pole, attached to anexisting wheeled medications cart 60 d (FIGS. 7-9), or any of a varietyof other shapes, forms and mounting locations.

The embodiment of FIGS. 5 and 6 also includes a display device 70, aweight scale 72, a scanner 74 for identifying waste items and aplurality of apertures 78 configured to reveal openings to respectivecontainers 80.

With reference to FIGS. 7-9, some embodiments of a station can comprisea movable lid 82 with a single aperture 84. The lid 82 can besubstantially flexible such that it can be driven to translate above thecontainers in order to selectively provide access to any one of thecontainers below the lid 82.

In some embodiments, the sorting machine can be configured to provideaccess to an appropriate container in other ways, such as by tilting,raising, lowering, pivoting, translating or otherwise moving a containerrelative to the machine in order to present the container opening to auser.

FIG. 10 illustrates an embodiment in which a sorting station comprises aseries of hinged sleeves 86 configured to pivot relative to a fixedportion of the sorting station. Each sleeve 86 is generally configuredto temporarily house a disposable container 80. The station 60 ecomprises a series of actuators configured to pivot each sleeve 86 andits associated container 80 outwards, thereby exposing the containeropening 88. In one embodiment, an actuator 90 can be located adjacent anupper portion of a container 80 and can be configured to push the upperportion of the container outwards from the station. Alternatively thesleeve 86 can be biased outwards by a spring or simply by gravity, andan upper actuator can be configured to release the sleeve/container toallow it to pivot outwards to open. The upper actuator can then pullinwards to return the container/sleeve to a closed position.

Alternatively or in addition, a lower actuator 92 can be providedadjacent a bottom portion of the container/sleeve combination. In oneembodiment, a lower actuator 92 can comprise a drive axle 94 rigidlymounted to the sleeve 86. The axle 94 can be driven by a motor or othermechanism in order to pivot the sleeve 86 inwards and outwards. Acontainer 80 can be inserted into the sleeve 86 and pivoted back so thata fixed portion of the station 60 e covers the container opening 88.During use, the actuator 90 or 92 causes the sleeve 86 to pivot outwardfrom the station 60 e, thereby exposing the container opening for use.The container 80 can be removed by sliding it out of the sleeve 86. Inan alternative embodiment, the above system can be provided without asleeve 86 by incorporating an actuator and a pivot point into thecontainer itself. In further alternative embodiments, other actuators,drive mechanisms, etc can be used in order to selectively provide accessto a container opening.

In another embodiment, the station can be configured to house each ofthe containers in a sliding drawer. The drawers can include actuatorsconfigured to move the drawer outwards until an opening is exposed. Thecontainers can then be easily removed once they are full.

FIGS. 11 and 12 illustrate another embodiment of a waste sorting anddisposal station 60 f in the form of a convertible rolling cart. In afirst orientation, illustrated in FIG. 11, the station 60 f is atwo-sided rolling cart. The station 60 f of this embodiment can beprovided with a hinge 96 configured to allow the two sides 98 a, 98 b ofthe cart 60 f to unfold into a one-sided arrangement. In this secondconfiguration (shown in FIG. 12), the station can be mounted or placedagainst a wall.

In some embodiments, a sorting and disposal station 60 can include ascale configured to determine a weight of a full container. Thus, ascale 72 can be provided on an upper or other accessible portion of thestation. Alternatively, the station can include a scale (e.g., a loadcell) to continuously or repeatedly weigh each container within thestation. Such information can be useful in creating a manifest for thecontainers before transportation of the containers to an appropriatedisposal facility. Additionally, or alternatively, a station can includea fill level sensor for continuously or intermittently determining afill level of a container. Embodiments of a fill-level sensor aredescribed in further detail below.

Disposable Containers

In some embodiments, the disposable containers are generally designed tobe low cost, yet include features that provide a functional interfacewith mechanisms in a sorting station to perform several desiredfunctions. For example, in some embodiments, each container includes adoor or lid which can be opened and closed automatically in order toallow or prevent access to a particular container at a particular time.Additionally, the containers can be configured to interface with sensorsfor determining a quantity of contents within the container, and/orsensors for determining a type of container.

In some embodiments, the containers 80 are blow molded (or otherwiseformed) from polypropylene, high molecular weight polyethylene,polyvinylchloride or any other suitable plastic or other material asdesired. In some embodiments, the containers 80 have substantiallyfrosted or translucent side walls. The containers will typically besized to have an internal volume of anywhere from 1 to 20 gallons,however greater or smaller volumes can also be used as desired. Forexample, in some particular embodiments, containers can be provided in1-gallon, 3-gallon and 8-gallon sizes.

The shape of the containers can vary widely. In some preferredembodiments, the containers include a lifting handle, a primary openingwhich can be automatically and/or manually closed or sealed, and abottom surface configured to allow the container to stand upright.Additionally, the disposable containers can also include features suchas an automatically-openable door or lid, a manually closable lid,features for accurately locating the container in a containercompartment of a station, a viewing window for visually verifying a filllevel, and/or identification information for informing a user of acontainer's contents (or intended contents).

The containers can be provided with an opening 88 having a variety ofshapes and/or features. For example, in one embodiment, the opening 88is substantially circular and has a minimum internal diameter of atleast about three inches (˜76 mm). In other embodiments, the opening 88can be substantially elliptical, rectangular, polygonal or otherwiseshaped, and can be any suitable size, including sizes smaller than threeinches in diameter. The particular type or types of waste to bedeposited in a particular container can be a significant factor that canbe used in determining a suitable size and/or shape of a containeropening. In general, the container opening should be sized to easilyaccept the largest waste item that is expected to be deposited in thecontainer. For example, some containers might receive full or partiallyfull liter-sized IV bags, gallon-sized biohazard bags or other largeitems. It is generally desirable that the container opening beconfigured to accept these large items easily and without tearing thebags or otherwise damaging or causing spillage of a waste item. Theskilled artisan will recognize that other factors may also affect achoice of container opening size or shape.

In some embodiments, disposable containers are provided in a pluralityof types, each type corresponding to a respective waste category orwaste classification. In order to allow clinicians, maintenance people,and any other persons who may handle the containers to quickly andeasily differentiate containers of various types, the containers can becolor-coded to correspond with a particular type or category of waste.In some embodiments, a color-coding scheme can be selected to matchindustry standards for various types of medical waste. Red, for example,typically signifies infectious waste, while yellow typically signifieschemo therapy drugs. Color-coded containers can advantageously simplifythe tasks associated with manual transportation and processing of thecontainers, and can aid in insuring that such tasks will be handledcorrectly for each waste stream.

Alternatively, such visual verification of a container's type can beprovided by any other suitable method. For example, the variouscontainer types can be indicated by labels bearing numeric,alphanumeric, graphical or symbolic information. Such labels can includeprinted stick-on labels or various features molded or formed directlyinto portions of the containers themselves. If desired, suchtype-identification features can be provided in addition to color-codingof the containers in order to further simplify identification of acontainer's type. Providing simple visual verification of a givencontainer's type advantageously simplifies and facilitates handling ofmedical waste materials throughout many aspects of collection anddisposal.

In some embodiments, the containers can be configured in such a way thata sorting and disposal station can automatically identify a type ofcontainer. Such automation allows a station/machine to detect the mixand arrangement of container types in the station at any given time. Insome embodiments, each container includes an identification key that canbe read by corresponding structures in a sorting station. The keygenerally allows the sorting station to automatically identify the typeof each container occupying a compartment or container position withinthe station. As discussed above, the station can be configured toidentify container types in either a static or dynamic mode depending ona desired degree of flexibility for a given station.

Identification keys may be physical features such as fingers molded intoor attached to each container. Alternatively, identification keys can beholes, notches, or grooves molded or cut into a portion of eachcontainer. In some embodiments, identification keys includeoptically-readable features such as holes, dark or light colored dots,text, symbols, graphics, etc. A physical key may be configured to beread by mechanical or optical switches associated with each compartmentor container position within the station. For example, FIG. 13illustrates an embodiment of a container 80 with an identification key104 made up of a series of holes 110 in a flange 112 extending from anupper portion of the container 80. The holes 110 of FIG. 13 can bedetected by a plurality of optical switches 138 mounted to a portion ofthe station adjacent a container position. Thus the various containertypes can be identified by providing holes (or other features) invarying combinations and positions.

Alternatively, a key may be an optical mark, such as a bar code, thatcan be interpreted by a sensor such as a bar code reader. Alternativelystill, the key may be a radio frequency identification (RFID) tag thatcan be read by a transponder associated with each compartment. In stillfurther embodiments, container identification keys can comprisemicrochips, magnetic strips, or other electronic media that can be readby a waste sorting and disposal station into which the container isplaced. In one alternative embodiment, a polychromatic sensitive opticalsensor can be provided to directly determine a color of a container.

As discussed above, some embodiments of a disposable container areprovided with automatically operable doors. In such embodiments, acontainer can be closed by default to prevent insertion of items into anincorrect container. Then, once an item is scanned or otherwiseidentified, the station can open the appropriate container or otherwisesignify the single correct container to receive that particular wasteitem.

FIGS. 14-17 illustrate embodiments of containers comprisingintegrally-formed automatically operable doors and correspondingstructures in a sorting station. The illustrated structures aregenerally configured to provide an automated interface between acontainer 80 and portions of a sorting and disposal station in order toallow the station to automatically recognize and operate a container.According to these illustrated embodiments, each compartment includes anactuator mechanism configured to automatically and selectively open andclose the corresponding container 80. The selective opening and closingof each container may be accomplished via interaction of structures onboth the disposable container and the station, and can ultimately becontrolled by a computer system within the sorting and disposal station.

In some embodiments, a container may include a movable lid molded orotherwise joined to the container opening. The lid can generally beconfigured to pivot, slide, hinge or rotate relative to a container inorder to reveal or cover the container opening. In some embodiments, thelid is configured to mate with a mechanical actuator in the station uponinstallation of the container in a given container compartment. Theactuator can be configured to cause the lid to open and close bytranslating, rotating or pivoting the lid. The actuator and lid can befurther configured to separate from one another when the container isremoved from the station.

FIG. 13 illustrates one embodiment of an interface between a container80 and portions of a sorting station. In the illustrated embodiment, thecontainer 80 comprises a gate 116 covering an opening 88 and configuredto slide in tracks 118 between an open position and a closed position.The gate 116 can include a latch 120 configured to lock the containeropening when the gate 116 is completely closed. When a new container 80is inserted into a station, a drive pin 122 on the gate control arm 124is engaged by the gate 116 of the container. The control arm 124 isconfigured to open and close the gate 116. The gate control arm 124 canbe coupled to a drive motor 128 via a transmission element such as adisc 132 or a similarly functioning arm. If desired, a position switch134 can also be provided on the disc 132, control arm 124, gate 116 orother component in order to detect a position of the gate 116. In theillustrated embodiment, the position switch 134 is an optical switchconfigured to detect one or more holes 136 in the disc 132.Additionally, the sorting station can include a plurality of opticalswitches 138 for detecting the presence of a container and/or the typeof container 80 inserted into the sorting station. The embodiment ofFIG. 14 replaces the gate control arm 124 of FIG. 13 with a slot 140 inthe gate 116 in order to convert the rotational motion of the pin 142extending from the disc 132 into linear motion of the gate 116.

In alternative embodiments, other configurations of automaticallyopenable doors/gates can be provided For example, FIG. 15 illustrates analternative embodiment of a container comprising a sectioned door 150configured to slide along tracks 152 extending from the exterior surfaceof the container 80. The slidable lids of the above embodiments can beprovided with a latch (such as that shown in FIGS. 13 and 14) which canbe automatically engaged in order to lock the container once a sortingstation determines the container is full. The embodiment illustrated inFIG. 16 can include a slidable door 116 driven by a rack and piniondrive mechanism 156. Alternatively, the drive mechanism 156 of FIG. 16can comprise a driven friction wheel configured to engage a portion ofthe slidable lid 116. A similar pinion or friction wheel drive systemcan be used to automatically operate the sectioned door 150 of theembodiment shown in FIG. 15. FIG. 17 illustrates an embodiment of acontainer 80 with a lid 158 configured to open by pivoting relative tothe container 80. In further alternative embodiments, a door can beopened or closed by any of a variety of other mechanisms. For example,worm screws, pneumatic pistons, hydraulic pistons, solenoids, or anyother motion-transferring mechanism can be used to selectively open andclose a container door.

In some embodiments it may also be desirable to provide an outer lidconfigured to seal a container opening once the container is full. Theouter lid is preferably configured to attach to the containersufficiently securely to prevent spillage or tampering. An outer sealalso shields users from contaminants that may have come in contact withthe container top area during use. For example, in some embodiments aflexible lid can be configured to seal over a top of the automaticallyactuated door by frictionally engaging a lip, groove, or other structurein a manner similar to many flexible lids used in food storagecontainers. In alternative embodiments, outer seals can be provided inthe form of a bag or shrink-wrap material that surrounds a substantialportion of a container's exterior.

In some embodiments, it may be desirable to provide a containerconfigured to render waste items non-recoverable by providing asubstance within an “empty” container that can react chemically withwaste items. In another embodiment, a solidifying agent can be providedwithin a container in order to solidify non-hazardous pharmaceuticalsallowing for their disposal in a landfill. In some embodiments, suchsolidifying agents can include materials capable of absorbing a quantityof a liquid non-hazardous pharmaceutical material. For example, suchabsorbent materials can include ceramic materials, sponge materials orother porous materials. Alternatively, such solidification may involve achemical reaction between the waste material and a substance providedwithin the container.

Fill-Level Detection System

In some embodiments, it is desirable to measure a fill level of wastewithin a container throughout the sorting and filling process. In someembodiments, such fill level sensing can be performed by measuring aweight of a container, such as by using a load cell, balance, or otherweight measurement device. In further embodiments, float systems can beadapted for use in determining a level of a waste material in a wastesorting system. In some cases, it is also desirable to perform such filllevel measurements without the sensor physically contacting thecontainer or the container contents.

In some embodiments, a piezo transducer can be used to determine avolume of air remaining in a container by conducting a frequency sweepof the transducer to determine the resonance of the air in thecontainer. Once the volume of air in the container is known, the airvolume can be subtracted from the known total container volume to obtainthe volume occupied by the container contents. In another alternativeembodiment, a distance-measuring sensor (such as SONAR, RADAR or opticaldistance-measuring sensors) can be located above and directed throughthe opening of the container in order to determine a “height” of thecontainer contents. In another embodiment, a sensor can be provided fordetermining whether a container includes any waste at all. Such a “wastepresence” sensor can be used in combination with a timer to determine areplacement schedule for a particular container based on a maximumacceptable dwell time for a particular waste item in a container. Stillother embodiments may use optical sensors to measure a fill level of acontainer.

FIGS. 18-19 illustrate one embodiment of a level sensor which can beused to automatically determine a fill level of a container using anoptical method. As shown in the schematic illustration of FIG. 18, oneembodiment of a fill level sensing system comprises a light source 230and a light detector 232 positioned on opposite sides of a disposablecontainer 80. In alternative embodiments, the light detector 232 neednot be located immediately opposite the light source, for example, insome embodiments the detector can be located on a wall adjacent to thesource 230. The sensor system of FIGS. 18 and 19 generally operates onthe principle that an “empty” container will permit more light to passfrom the source, through the container, and to the sensor than will a“full” container. This is simply due to the fact that the contents ofthe container 80 will absorb and/or reflect a substantial portion of thelight which enters the container from a light source.

As used herein, the terms “empty” and “full” shall be given theirordinary meaning and shall be used to define relative amounts of debris,or other matter, in a container. For example, in certain embodiments,the sensor may indicate that the container is ready to be emptied ordiscarded, not because it is completely saturated, but because it hasreached the desired point of fill or saturation. In some situations, itmay be desirous to empty or remove a container when anywhere from about1% to about 100%, often from about 25% to about 100% of that containercontains waste material. In other situations, it may be desirable toremove a container when about 50% to about 95% of its volume is occupiedby waste material.

In some other embodiments, a parameter other than weight or filledvolume may be used to determine when a container is “full.” For example,in one embodiment, a sensor to detect radioactivity is used to determinethe amount of radioisotope in a container or receptacle. Theradioactivity sensor may used in connection with a fill sensor, or itmay be used alone. Thus, in some embodiments, a container may beemptied, discarded, or replaced based on a certain amount ofradioactivity, rather than (or in addition to) the surface area, volume,weight, density and/or another parameter of the material in thatcontainer.

In yet another embodiment, a sorting and disposal system can be providedwithout any automatic level detection apparatus. For example, in such anembodiment, the containers can be configured to allow a clinician,maintenance person, or other user to visually verify a fill level of thecontainer. In such embodiments, the containers can be made of asubstantially transparent or translucent material. Alternatively, thecontainers may be substantially opaque but can include a transparentviewing window to allow visual verification of a fill level. Suchviewing windows could extend substantially an entire height of thecontainer, or could extend only a height of a desired portion of thecontainer.

In some embodiments, the source 230 and detector 232 are located along a“fill line” which generally defines a “fill plane.” The fill plane 240is generally the level within the container 80 which a processor 242defines as “full.” In some embodiments, the actual free surface ofcontents within a container may not necessarily be planar. In suchembodiments, the “fill plane” used by the processor and fill levelsensing system is simply an average height of the material.

In the embodiment illustrated in FIG. 18, a light source 230 is locatedat a “front” of the container and a detector 232 is located at a “rear”of the container. In alternative embodiments, the positions of the lightsource 230 and detector 232 can be reversed, or positioned at any otherposition around the container 80. In still further embodiments, multiplesources and/or detectors can also be used as desired.

As discussed above, the containers 80 are typically made of atranslucent material which allows at least some amount of light to passthrough its walls. The embodiments of a fill level sensor illustrated inFIGS. 18 and 19 are particularly advantageous when used to measure afill level of a container with translucent sidewalls. However, theskilled artisan will recognize that certain advantages of theembodiments described herein may be advantageously applied to systemsusing containers having transparent sidewalls or containers withtransparent windows in otherwise relatively opaque sidewalls. As usedherein, the term “translucent” is used in its ordinary sense and referswithout limitation to a material which allows the diffuse transmissionof light when illuminated, while remaining substantially non-transparentwhen not illuminated.

The light source can comprise any suitable source of light such asincandescent bulbs, white or colored LED's, or other sources. In someembodiments, the light source 230 is located such that it is verticallycentered on a desired “fill line” 240 of the container. The light sourcecan be laterally centered relative to the container, or can comprise awidth that is about as wide as the container 80. In still furtherembodiments, a plurality of light sources can be used to illuminate acontainer from multiple points.

As illustrated in FIG. 19, the light detector 232 can comprise an arrayof photo detectors 236 such as cadmium sulfide photo detectors orphotodiodes. In the illustrated embodiment, the array of photo detectors236 comprises three rows 244, 246 and 248 of detectors 236. The upperrow 244 contains a single detector 236 while the middle 246 and lower248 rows contain a plurality of detectors 236 (three in the illustratedembodiment). In alternative embodiments, the upper row 244 can beprovided with additional detectors which equal or exceed the number ofdetectors in the other rows. Similarly, the middle 246 and lower 248rows can include fewer or more than three detectors as desired. Thenumber of detectors in each row will typically be determined by thealgorithm used to determine the fill level of the container and/or thedegree of accuracy desired. In some embodiments, it may also bedesirable to provide more than three rows of detectors. For example, insome embodiments, a fill level detection system can be provided withfour, five or more rows of detectors.

In some embodiments, the middle row of detectors is positioned to liejust above the fill line 240 of the container 80, and the lower row 248of detectors 236 is positioned just below the fill line 240. The upperrow 244 of detectors 236 can be located substantially above the fillline, and can be used to calibrate the detectors middle 246 and lower248 rows as will be described in further detail below.

In some embodiments, the upper and middle rows can be spaced by adistance 250 of between about ±2″ and about 2 inches, in otherembodiments the upper and middle rows can be spaced by a distance 250 ofbetween about 1 inch and about 1½ inches, and in one particularembodiment, the upper and middle rows are spaced by a distance 250 ofabout 1{fraction (1/4)} inches. Similarly, the middle and lower rows canbe spaced by a distance 252 of between about ½″ and about 2 inches, inother embodiments, the middle and lower rows can be spaced by a distance252 of between about 1 inch and about 1½ inches, and in one particularembodiment, the middle and lower rows are spaced by a distance 252 ofabout 1¼ inches. In some embodiments, the detectors 236 of the middle246 and lower 248 rows are spaced horizontally by a distance 254 ofbetween about ±2 inch and about 3 inches, in other embodiments, thedetectors 236 of the middle 246 and lower 248 rows are spacedhorizontally by a distance 254 of between about 1 inch and about 2inches, and in one particular embodiment by a horizontal distance 254 ofabout 1½ inches. In some embodiments, the sensors are evenly spaced,while in other embodiments, the sensors of the middle row arehorizontally spaced differently than the sensors of the lower row. Infurther alternative embodiments, the spacing of the detectors 236 can bedetermined by factors such as the size of the container or the materialto be placed within the container.

In operation, the individual photo detectors 236 pick up lighttransmitted through the container and output corresponding signals to aprocessor 242. On one hand, the light intensity arriving at thedetectors 236 depends on the fill level of the container 80. Inaddition, a number of secondary factors also effect the light intensityreaching the detectors 236. These include the strength of the lightsource 230, the color and opacity of the container 80, the amount ofambient light, and other factors such as dust in the air. The lightintensity at the top detector row 2244 is almost completely governed bythese secondary factors, since it is located well above the fill line240. By contrast, the light intensity arriving at the middle 246 andlower 248 detector rows will be effected more by the fill level of thecontainer contents as the container 80 becomes more full (e.g., as thefill level approaches the fill line).

When the container 80 is empty and the overall light intensity isgreatest, a baseline reading is recorded and calibration coefficientsare generated for each of the detectors 236 and detector rows 244, 246,248. As the container fills, the received light reaching the detectorsdecreases slightly as material in the container blocks a portion of thediffused light transmitted through the container 80. During this phase,the top detector reading is used to compensate the readings of themiddle and lower detector rows accordingly. When the container contentsreaches the fill line, the bottom row of detectors will be blocked bythe container contents, while the middle 246 and upper 248 detector rowsremain unobstructed. This results in a substantial drop in the lightintensity reaching the bottom row 248 of detectors, and correspondingly,a substantial difference in signal strength between the middle 246 andlower 248 detector rows. When this signal difference reaches apre-determined threshold level, the processor determines that thecontainer is “full.”

In some embodiments, the items being deposited into a container may bestacked unevenly or oddly oriented within a container so that thecontents of a container vary from a neat horizontal fill level. Forexample, some large items, such as syringes or other contaminatedmedical devices, may stack oddly within a container, thereby creatingvoids of unfilled space in a central portion of a container, above whichwaste items may be stacked. Such variations in filling can lead to leadto measurement errors. Thus, in some embodiments, a level sensing systemcan be provided with error processing capabilities to account forvariations in orientation and/or uneven loading of a container.

For example, in some embodiments, the signals from the plurality ofdetectors in each row are averaged to provide a consensus value for therespective detector row. This advantageously allows the processor todetermine an average fill level in the event of an uneven fill surface.For example, in an idealized case, a container filled with a pluralityof spherical particles through a hole in the top center of aregularly-shaped container will typically have a free surface in a shapeof a cone with a peak at the center, and dropping off evenly in eachdirection. In such a case, the center detector of the lower row 248 willtypically receive a lower light intensity than the detectors on eitherside. Thus, by using the data from all of the detectors in a horizontalrow, a processor can calculate an approximate average fill level inorder to prevent over-filling of the container.

These or other error-processing techniques can also be used tocompensate for manufacturing defects in a container that might result inerroneous results. For example, if a plastic container wall comprises anair bubble or a dark spot in a region adjacent one or more of thedetectors, these abnormalities could cause erroneous readings by thosedetectors. To compensate for this, a system may give less weight (or noweight at all) to signals from detectors that are out of a statisticallyexpected range of variation from the remaining detectors. By taking anaverage signal across all detectors in various combinations and/or byassigning varying weights to individual detectors, a control algorithmcan teach itself to recognize and adapt to such error-causing situationsin order to obtain consistent readings.

In some embodiments, the functionality of a fill level sensing systememploying a light source and a plurality of optical detectors canadvantageously be enhanced by containers with “frosted” or translucentwalls. Another advantage of certain embodiments of a level sensingsystem as described herein is that such systems can be polychromaticsensitive (i.e. configured to sense light of various colors withconsistent accuracy). Thus, in addition to measuring a fill level of acontainer, the above-described sensors can be configured to determine acolor of a container (each container color being associated with aparticular container type as discussed above). In some embodiments,these and other advantages are achieved through the use of cadmiumsulfide photosensitive cells. In alternative embodiments, optical levelsensors can be constructed using other optical detectors, includingother photoconductive cells, photo diodes, or other sensors capable ofdetecting light in the visible or infrared spectrum.

In some embodiments, each one of a plurality of fill-level sensors iscontrolled by a single processor in a waste sorting system. In oneembodiment, a plurality of photo detector arrays can be connected to asingle multi-channel bus, and a plurality of light sources can becontrolled by a processor. In this embodiment, the processor canilluminate a single container at a time. Thus, the detectors behind eachof the “dark” containers would be at high impedance, and would thereforebe out of the circuit.

In some embodiments, a fill level sensing system employing opticalsources and detectors can include an additional photo detector that isgenerally configured to measure changes in “ambient” light within thesystem in order to appropriately adjust the readings from the detectorarrays measuring fill level. An ambient light detector can comprise asingle optical detector, or a plurality of detectors in a circuit. Inone such embodiment, an additional ambient light detector is providedwithin a waste sorting system in a location selected to measure anylight entering the system from the exterior of the sorting system. Forexample, the ambient light detector can be located adjacent acontainer-replacement door or any other portion of the system that isopen to external light.

FIG. 22A illustrates one embodiment of a circuit schematic which can beused in building an optical fill level sensor such as that illustratedin FIGS. 18 and 19. The skilled artisan will recognize that this ismerely one exemplary schematic, and that alternative embodiments of thesystem of FIGS. 18 and 19 can be built using any appropriate components.

FIGS. 20-22 are flow charts illustrating embodiments of softwarealgorithms used by a level detector for use in a sorting system. FIG. 20is a flow chart illustrating an overview of a level testing algorithm.When the system determines that a new container has been inserted, thelevel sensor establishes new baseline values for the detectors in orderto define the “empty” state. The level sensing system then reads valuesof the detectors 236 and inputs the detector values to an inferenceengine (FIGS. 21 and 22).

The inference engine can use a “fuzzy logic” method similar to theSugeno method. In one embodiment, the inference engine uses a table ofempirically-determined data to establish rule weights. The inferenceengine can also use multiple grouping of detectors in addition toindividual detector levels to calculate a final fill level of thecontainer. In some embodiments, the empirically-determined lookup tablecan be developed by performing various calibration experiments using anoptical level sensing system to measure containers at known fill levels.In addition to any controlled experiments, the lookup table can besupplemented by analysis of information it receives during use inmeasuring fill levels of new containers. For example, as opticalanomalies are detected and accounted for, the software can adapt tocorrect for them.

FIGS. 21 and 22 are flow charts illustrating one embodiment of aninference engine. In order to avoid misleading readings during filling,the system can be configured to determine when the detectors are at asteady state (e.g., when the movement of waste within the containerdrops below a threshold level). This is particularly helpful inembodiments in which a waste material is a liquid, and thus may continuemoving for a period of time.

Once steady state is reached, the inference engine compares the valuesof the detector readings and ultimately derives a final fill value whichcan be stored and/or output to a user-readable device such as a liquidcrystal display. In alternative embodiments, an output of the system caninclude other visible, audible or tactile alerts, such as LEDs, buzzers,bells, vibrators, etc. In some embodiments, an output signal is used tonotify the user that a particular container is ready to be emptied,discarded, replaced etc. In an alternative embodiment, an output signalis provided substantially continuously or at various intervals, so thatthe user can determine or monitor the amount of material in a givencontainer at any given time. For example, in some embodiments, thefill-level of a container can be measured at regular intervals, such asevery ten minutes, every hour, every two hours, every six hours, every12 hours, or every 24 hours. In still further embodiments, the systemcan comprise a sensor (such as an optical sensor) to determine when anitem is deposited into a container. Then a fill-level of the containercan be measured after each item is deposited in the container.

FIG. 23 illustrates an alternative embodiment of a video fill levelsensing system. The embodiment of FIG. 23 employs a camera 270 tocontinuously detect an intensity of light exiting the container from thesource. In the illustrated embodiment, a light source 270 is positionedto illuminate the container 80, and a curved mirror 274 and pinholevideo camera are located adjacent another side of the container 80. Thesystem can also include a software-based processor 276 and otherelectronic hardware. In the illustrated embodiment, the light source 270is located adjacent one vertical side of the container 80 and the cameraand mirror are positioned on the opposite side of the container. Inalternative embodiments, the light source 270 and camera/mirror assemblycan be located on adjacent sides of the container 80. Alternativelystill, the light source 270 can be located above the container such thatlight is directed downward into the container, thereby allowing thewaste to absorb as well as reflectively diffuse the light source ontothe walls of the container 80.

In some embodiments, the camera 270 is directed at the mirror 274 todetect light emitted from the container 80 and gathered by the mirror274. The curved mirror 274 provides a linearization of scanline width bydistorting the optics of the camera. In one embodiment, the camera 270is a pinhole camera, which is selected due to the depth of field thistype of lens provides. In one embodiment, the curved mirror 274 has ashape substantially similar to a shoehorn, e.g., it is curved about twoperpendicular axes (e.g., longitudinal and transverse axes). Alternativemirror configurations can also be used as desired. The particularcurvature of the mirror 274 is determined empirically depending on thewidth of scanline needed and the height of the measured area (e.g.,. theheight of the container wall). Variation in the curvature of the mirroralong its length allows the scanline to be optimized in order toemphasize areas of higher interest and to de-emphasize lower interestareas. The mirror can be convexly curved at the height of higherinterest areas, and concavely curved to de-emphasize lower interestareas.

In some alternative embodiments, the light source can include bands ofvarying color or intensity along the height of the container in order toprovide emphasis to portions of the container, or to provide “watermark”levels that can be measured against. In some embodiments, the softwarecan be configured to interpret information received from the camera tolearn about points of interest in order to further optimize ameasurement algorithm. For example, rather than programming an algorithmto anticipate areas of higher or lower interest, the algorithm can beconfigured to recognize variations in light intensity during calibrationin order to detect such areas of higher or lower interest.

The processor and its support hardware provide the sampling of multipleluminance intensities along the wall of the container 80 adjacent themirror 214. The analog video signal is amplified and ground-referencedby the video amplifier. This amplified signal is scanned for a selectedscanline to digitize for quantifying its luminance value. The amplifiedvideo is also applied to the Sync Separator module, which producestiming pulses for the scanline selector module. The processor receivesthe scanline data from the scanline selector, digitizer and syncseparator. The video level sensor can determine a current fill level ofthe waste in the container 80 using a similar software method to thatdescribed above with reference to FIGS. 18 and 19. FIG. 23A illustratesone embodiment of a circuit schematic which can be used in building avideo fill level sensor such as that illustrated in FIG. 23. The skilledartisan will recognize, however, that this is merely one exemplaryembodiment. In alternative embodiments, the system of FIG. 23 can bebuilt using any appropriate components.

Many of the above embodiments of fill level sensors were described withreference to a single disposable container. In some alternativeembodiments, it may be desirable to provide a single fill leveldetection system configured to selectively measure a fill level of anyone of a plurality of containers. For example, in one embodiment, alight source may be provided on a first side of a plurality ofcontainers, and a light detector can be movable into a position oppositethe light source of the containers. In one embodiment, this may take theform of a circular arrangement of containers in which a light detectoris located at a center of a circular arrangement of containers. One ormore light sources can be positioned on an outer portion of the circulararrangement such that the light source and/or the light detector iscapable of measuring a fill level of each one of the plurality ofcontainers around the circle.

In some embodiments, the sorting system can also include a weight scale(such as a load cell, pressure transducer, mechanical scale or otherdevice) configured to weigh either a single spent drug, container orindividual segregated spent drugs. In one embodiment, the informationfrom the scale can be sent to a printer providing a means for printing amanifest for the container. Additionally, such information could becombined with other information available to a clinician in order todetermine a quantity of a drug or substance that has been used orconsumed. Many hospitals are automating the dispensing of drugs. Theautomation is usually embodied in a piece of equipment that a doctor ornurse accesses with a patient and clinician code and the correct amountof drug is dispensed. The automation provides pharmacists, nurses,doctors and administrators with information from a database on whatdrugs are dispensed and to which patient. These systems can typicallyindicate how much of a drug was administered, but entering thisinformation typically requires a clinician to return to the dispenser(which may be inconvenient, and thus not done regularly). Thisinformation can be quite useful because it will demonstrate anyinefficiencies or mistakes in administrating the drugs as well as pointout any theft of drugs. In some embodiments, a sorting and disposalsystem can be configured to track dispensing information because at thepoint of throwing the spent drug away, they are automatically providinginformation to a central database.

Sorting Algorithm

Embodiments of a pharmaceutical waste sorting and disposal system willgenerally employ a waste sorting algorithm to assign each item of wasteto a particular waste category and correspondingly to a particular wastecontainer. A waste sorting algorithm can take a variety of forms, andcan include a range of functionalities.

In some embodiments, as discussed above, determination of the wastecategories themselves can depend on a number of factors, including RCRAhazardous waste definitions, state and federal EPA regulations, OSHAregulations, and any institution-specific regulations. For example, RCRAdefinitions generally include a P list, a U list and fourcharacteristics of hazardous waste: ignitability, corrosivity, toxicityand reactivity. Materials exhibiting each of these characteristicstypically call for different handling, treatment and/or disposal. Thus,in some cases waste categories can be defined based on groups ofmaterials that require the same or similar handling, treatment, ordisposal. However, in some cases, two materials that may be handledand/or treated in a similar manner might react adversely if they arecombined with one another. Thus, in further embodiments, determinationof the waste categories can also depend on the combinability ofmaterials exhibiting one or more of the above characteristics.

Once a series of unique waste categories is established, lists of knownpharmaceuticals, chemicals, materials and waste items can be selectivelyassigned to at least one of the waste categories. In some embodiments,as discussed above, when a waste item is presented to a sorting station,the item is identified according to a waste item identifier. Suchidentifiers can include a trade name, a generic name, a National DrugCode (NDC), one or more components or ingredients of the item, or anyother sufficiently unique or relevant waste-identifying datum. Thus, acategory database can be developed which correlates a number of knownwaste identifiers with respective waste categories according to existingfederal, state, local, institution-specific or other rules andregulations.

In some embodiments, it may also be desirable to provide a databasewhich lists ingredients of a plurality of known pharmaceuticals or otherchemicals that have not yet been correlated to a waste category by thecategory database. Such an ingredient database can be used by thesorting algorithm in an intermediate step between identifying an itemand assigning the item to a category on the basis of one or moreingredients. In some embodiments, an ingredient database may residewithin the waste sorting and disposal system. In alternativeembodiments, an ingredient database can reside at a remote location,such as on a server operated by a manufacturer of a particular item, oranother remote location. The waste sorting and disposal system can beconfigured to access such remote databases via any available network,including the internet.

In some embodiments, on a first level, assignment of waste items towaste categories can be performed simply by sorting the items accordingto known characteristics. In some embodiments, a waste sorting algorithmsimply involves locating a waste item identifier in a look-up table ordatabase which lists known identifiers correlated to respective wastecategories, such as the category database described above. Thus, to theextent that an item can be assigned to a waste category based solely onone or more waste item identifiers, the sorting algorithm can comprise asimple look-up routine. If needed, the sorting algorithm may also seekadditional information such as from the ingredient database describedabove, or any other available source of additional information.

Cases may arise where a single waste item possesses two or more wasteidentifiers (such as ingredients) belonging to two or more differentwaste categories. Thus, in the event that a particular waste item canreasonably be assigned to two or more waste categories, yet is onlyphysically capable of being placed in a single container, the wastesorting algorithm can be configured to assign the item to a singlecategory by reviewing a number of secondary variables. Such secondaryvariables may include a dosage or quantity of specific ingredients; adilution or concentration level of one or more ingredients; a relativehazardousness level of one or more specific ingredients; a relativereactiveness of one or more ingredients; a shape, size, type or otherfeature of a waste item container (e.g., a pill bottle, syringe, etc); aphysical property of the item (e.g., liquid, solid or gas), or any otherdatum that may be available to a user, but that might not beautomatically determinable by the sorting station. If such a piece ofadditional information is needed in order to complete an assignment ofan item to a container, the sorting station can prompt a user to inputfurther information. Such additional information can be input byselecting from multiple answer choices or by typing.

FIG. 24 is a flow chart illustrating one embodiment of a sortingalgorithm. In the illustrated embodiment, a user initiates the processby presenting 300 a waste item to be identified by the sorting station.The sorting station then detects 302 a waste item identifier in anymanner discussed above, such as scanning a barcode, reading an RFID tag,or scanning a textual or graphic label. The system then searches 304 thecategory database using any information or identifier determined fromthe item in an attempt to discover whether the determined identifier haspreviously been correlated to a waste category. If the identifier isfound 306 to have been correlated to a waste category, the systemcontinues by assigning the item to the appropriate waste category, andfacilitating disposal of the item in the appropriate container.

On the other hand, if the identifier is not found in the categorydatabase (e.g.,. if the system discovers that the determined waste itemidentifier is insufficient to determine an appropriate waste category),the system may search an ingredient database 308 for additionalinformation or further details about the item. If additional informationis found 320 in an ingredient database, the additional information,along with the originally-detected waste item identifier can be used toagain search the category database 322. If this information is found tobe sufficient 324 to assign the item to a waste category, then thesystem assigns the item 326 to that category, determines an appropriatecontainer 328 and facilitates disposal 330 of the item in a containerassociated with the assigned category. The system can also store 340 theidentifier/category assignment combination in the category database foruse in accelerating the sorting of future waste items with the sameidentifier.

However, if the search of the ingredient database yields insufficientinformation to assign the item to a waste category, the system may seekadditional information by prompting a user 342 to input additionalinformation. Such a prompt may request specific information, such as achoice between known alternatives, or may be more general in nature. Theinformation received 344 from the user can then be combined withpreviously-obtained information about the item, and the categorydatabase can again be searched in an attempt to assign the item to acategory. If this information, in combination with thepreviously-obtained information, is sufficient to assign the item to awaste category 346, then the system assigns the item 326 and facilitatesdisposal 330 of the item in the appropriate container. As above, thesystem can also store 340 the identifier/category assignment combinationin the category database for use in accelerating the sorting of futurewaste items with the same identifier.

If the information received 344 from the user is insufficient 346 forthe system to make a category assignment, the system can either promptthe user for still more information 342, or the system can simply assign350 the item to the most conservative waste category for disposal of theitem as hazardous waste.

FIG. 25 illustrates one embodiment of a portion of a sorting algorithmwhich can be used in determining the best container for a particularitem. Once the sorting algorithm has assigned an item to a wastecategory, the system determines 328 the container type associated withthe assigned waste category. In the illustrated embodiment, the stationsearches the stock of the containers currently loaded into that stationto determine whether the assigned container type is present in thatparticular sorting station 360. If the container type is present, thestation proceeds to indicate 362 the appropriate container to the user,and the user may then deposit 330 the item into the selected container.However, in some embodiments, if the selected container type is notpresent, the station can assess 366 whether another sorting stationnearby contains a container of the assigned type. If a station with theselected container is nearby, the system can direct the user 370 to thenearby station to deposit the item. If a station with the selectedcontainer type is not nearby, the system can re-assign 368 the wasteitem to the most conservative (e.g., the highest level hazardous waste)category for which a container is loaded into the station.

In an alternative embodiment, a station may indicate that the selectedcontainer is full and thus cannot accept any further waste items. Insuch a case, the station can instruct the user to replace container withan empty one of the same type. Alternatively, the station can instructthe user to use a container in a nearby station. In some embodiments,the station may offer the user a choice between replacing a containerand using a nearby station.

The term “nearby” is a relative term, and can include any actualdistance deemed appropriate by a particular user or systemadministrator. For example, in some embodiments, a station located onanother floor of the hospital may be considered nearby, while in otherembodiments, a sorting station across the hallway may not be considerednearby for the purposes of re-directing disposal of the waste item.

In some embodiments it may be inappropriate or undesirable to re-assignan item to a higher level container in the event that an appropriatewaste category cannot be determined (e.g., as in step 350 of FIG. 24),or that an appropriate container cannot be located within an acceptableproximity (e.g., in step 368 of FIG. 25). In such embodiments, it may bedesirable to provide a temporary holding space for items that cannot beplaced in any currently present container. Such items can then beanalyzed at a later time by a hazardous waste analyst in order todetermine the most appropriate disposal of the item. Once such ananalysis is performed, the analyst preferably enters such informationinto the category database in order to facilitate future sorting ofitems having similar characteristics.

In some embodiments, the waste sorting software can be configured tomaintain a log file of all identified waste items and thecategories/containers to which each item was assigned. Such informationcan be used by hospital administrators, regulatory auditors,pharmacists, or other entities to determine what items were disposed ofand how. This information can be used to further optimize the sortingalgorithm, to audit compliance with regulations, to audit usage ordisposal of specific items, to alter a container arrangement in astation to increase sorting efficiency, or any of a variety of otherpurposes.

By enlisting the use of one or more embodiments of the present system,hospitals can demonstrate to their communities and their staff that theyare participating in the improvement of the environment. It has beendemonstrated by the US Geological Survey that the groundwater in theUnited States is contaminated with drugs. Although in trace amounts, thecumulative effect of these contaminants have been shown to be endocrinesystem disrupters contributing to the rise in cancers, birth defects andother ailments. By properly sorting the spent drugs into appropriatecontainers, the waste can be properly processed in order to leave onlyan inert residue that cannot contaminate the ground water.

Thus, embodiments of a medical waste sorting and disposal systemadvantageously provide a convenient means for clinicians toautomatically sort pharmaceutical waste streams in order to comply withRCRA without the need to manually classify and sort each itemindividually. Additionally, the system advantageously provides hospitalswith a means for participating in the improvement of the environmentwhile avoiding fines for non-compliant waste disposal methods.

Additionally, as described above, some embodiments of the system can beconfigured to create a manifest to provide administrators suitabletracking information on the amount of a drug that has been actuallyused. Many hospitals are now moving toward implementing drug dispensingautomation. The automation provides the hospital pharmacist andadministrator information on what drugs are dispensed but not aconvenient way of generating information on how much of a drug is used.

Medical Waste Treatment System

In one embodiment, a medical waste treatment system is provided. Themedical waste treatment system is a product that renders infectiouswaste non-infectious, compacts it to a fraction of the original volumeand uniquely maintains the treated material in a compact form. The costof present embodiments of a medical waste treatment system is much lessthan competing technologies, because the footprint of the equipment is,in one embodiment, about one fourth the size. Competing technologieshave cycle times that are long (usually about one hour) whichnecessitate large vessels for acceptable throughput versus the medicalwaste treatment system which has a cycle time of less than five minutes.

In one embodiment, the operating cost goal (about $0.09/lb) will beequal or better than most common technology, autoclave sterilization.Other competing technologies may have lower operating costs but theyhave many drawbacks. Incinerators have lower operating costs ($0.02/lb-0.04/lb) but it is possible that the EPA may tighten regulations andforce many of the remaining incinerators to shut down. Many states donot allow incinerators to operate within their boundaries. For example,much of California's infectious waste is trucked to a Kansas Cityincinerator. The transportation costs add to the actual operating costs.Plasma technologies have equipment costs that are very high ($1-$3million) and are, therefore, only suitable for central processingplants.

In one embodiment, a medical waste treatment system as a truck mountedservice to hospitals is provided. The medical waste treatment system hassignificant advantages over truck mounted chemical processors. Themedical waste treatment system unlike the chemical processors has aresidue that is substantially innocuous such as common sand. It has beendemonstrated that if there are any concentrations of organic matter,such as blood, the chemicals tend to be consumed by the organics leavingsome of the remaining waste in a load untreated or partially treated. Inone embodiment, the medical waste treatment system uses a unique heattechnology that quickly and uniformly decontaminates the wasteregardless of the amount of organics present. In several embodiments,the heat technology comprises use of sand or wax (including, but notlimited to, paraffin) or a combination thereof. In one embodiment, thesand and/or wax is heated to a temperature of about 150° C. to about250° C., preferably between about 165° C. to about 225° C. In oneembodiment, the sand and/or wax is heated for less than about fiveminutes. One particular advantage of this method is the ability toproduce highly stiff and/or compacted medical waste. In someembodiments, the volume and/or surface area of the treated medical wasteis reduced to about {fraction (1/10)} of its original size.

Up to about 50% of infectious medical waste can be plastic content, ofwhich about 25% can include disposable PVC waste. Utilizing sand or waxto treat such plastic waste may not be any more cost effective than anAutoclave or other processing approach for these materials. It also maycause a number of problems such as the PVC outgassing chlorine becausethe temperature may be greater than 320 degrees ° F. (the effectivemelting temperature of PVC).

Thus, in one embodiment, a potential processing system for such plasticwaste includes a rough grinder to grind the heterogeneous infectiousmedical waste into 2″ by 5″ strips. A second grinder grinds the wasteinto small pellets that are less than 0.25″ in diameter. The wastepellets are mixed with a whitening agent and moisture that in thepresence of UVC and/or UVA will cause an oxidative reaction which inturn will denature protein or organics, thereby inactivating some if notall of the microorganisms or spores present in the pelletized waste.This will set up the microorganisms and spores for a shortersterilization procedure

In some embodiments, the moisture can be removed by a desiccant dryerthat may be heated and then conveyed to a hopper of a plastic extruder.The extruder can be set to temperature less than 320 degrees F. but hotenough to melt the PVC. Plasticizers and other additives may beintroduced to get the heterogeneous pelletized mix of waste to flowhomogeneously and not clump or dissociate. This process is also thefinal sterilization procedure. Many of the states have adopted adocument called the STAAT II sterilization guideline that spells out theamount of reduction of spores and microorganisms required forsterilization.

In some embodiments, the effluent from this plastic-treating processcould then be used as a filler for a product that is extruded ratherthan being placed in a land fill. Reducing disposal of solid waste isdesirable because of the cost (0.02 to 0.05 cents per pound). One suchproduct is a security fence that is composed of a hollow extrusion thatforms posts and walls. The center is filled with extruded hospital wastethat will provide the hollow extrusion with more weight and structuralintegrity. In another embodiment, a sandwich of compressed mylar sheetscan be applied to the exterior of the fence to render the wall bulletresistant or proof.

Other embodiments are possible, for example freeway dividers, caskets,ashphalt filler for roads or any proprietary design that incorporatespreviously extruded hollow profiles that are filled with the extrudedsterilized infectious medical waste can be used.

Medical Waste-Water Monitoring System

In one embodiment, a medical waste water management system is provided.In one embodiment this system is a water quality sampling service thatis supplied to hospitals, clinics and labs. The product would beinstalled at the P trap of a sink. The medical waste-water monitoringsystem would sense water draining, and a sample of water would bedirected to a cuvette on a carousel. The samples could be taken randomlyor in some predetermined sequence at a number of different sinksthroughout a facility. The carousel of cuvettes would be removed, andthen sent to an inside or outside lab for analysis. The analysis wouldpinpoint the location of any water pollution. Training classes toreinforce the proper disposal of pharmaceuticals are provided accordingto one embodiment of the invention. The service would continue on a lessfrequent basis once clinician habits had improved.

Despite a plethora of federal, state and local regulations, manyclinicians continue to inappropriately dispose of pharmaceuticals in thesink. This is especially true of pharmaceutical spiked IV fluids.Verification of this practice has been established in a recent marketresearch effort with 150 hospitals in which 60% of the respondentsadmitted to inappropriate disposal of drugs down the drain.

One advantage of several embodiments of this system is that it canpinpoint the source of the infraction. By combing this service alongwith the other Company products and services, the Company will have asustainable competitive advantage.

Air Quality Monitoring System

The air quality monitoring system is a service that utilizes a device tosample the air quality, primarily in the pharmacy, oncology andoperating room areas. It is intended to detect hazardous drugs includingchemotherapeutics and anesthetics that become volatilized. The serviceis intended to provide clinicians with drug specific air qualityinformation. The service will also suggest ways of eliminating thecontaminants with both devices and a change in protocol. One advantageof some embodiments of this approach is that drug specific informationthat can be obtained.

Hospital Hazard Prevention

According to the Bureau of Labor Statistics, hospitals and nursingfacilities are among the most hazardous work environments. Each year, anaverage of seven occupational injuries or illnesses out of 100 employeesoccurs. About half result in lost work time. Working with or exposure totoxic chemicals is the single largest contributing risk factorassociated with occupational injury and illness in healthcare

Although nanoemulsion disinfectants and microfiber materials forcleaning and disinfection have worked successfully to reduce toxicity,much opportunity remains to improve the hospital environment, making itsafer for the healthcare worker. Reducing hospital hazards will alsoresult in savings to the hospital.

In one embodiment, a system for a service to analyze and implementreductions in hospital hazards is provided. Implementing the solutionswith hospital personnel will be a process similar to making costreductions in organizations with significant numbers of administrativeprocedures.

Although certain embodiments and examples have been described herein, itwill be understood by those skilled in the art that many aspects of themethods and devices shown and described in the present disclosure may bedifferently combined and/or modified to form still further embodiments.Additionally, it will be recognized that the methods described hereinmay be practiced using any device suitable for performing the recitedsteps. Such alternative embodiments and/or uses of the methods anddevices described above and obvious modifications and equivalentsthereof are intended to be within the scope of the present disclosure.Thus, it is intended that the scope of the present invention should notbe limited by the particular embodiments described above, but should bedetermined only by a fair reading of the claims that follow.

1. A method of sorting medical waste, the method comprising, in noparticular order: receiving an identifier associated with waste to bedisposed of; retrieving, based on the identifier, information from adatabase, the information being derived from applicable rules regardingdisposal of waste items; assigning the waste to a disposal categorybased on the information retrieved from the database; locating acontainer associated with the assigned disposal category; andfacilitating disposal of the waste item into the container associatedwith the assigned disposal category.
 2. The method of claim 1, whereinthe identifier is a common name of the waste item.
 3. The method ofclaim 1, wherein the identifier is a chemical name of the waste item. 4.The method of claim 1, wherein the identifier is a National Drug Code ofthe waste item.
 5. The method of claim 1, wherein facilitating disposalcomprises providing access to a container opening.
 6. The method ofclaim 5, wherein providing access to a container opening comprisesopening a door.
 7. The method of claim 5, wherein providing access to acontainer opening comprises opening a drawer which houses a container.8. The method of claim 5, wherein providing access to a containeropening comprises pivoting a sleeve which houses a container.
 9. Themethod of claim 5, wherein providing access to a container openingcomprises opening a door.
 10. The method of claim 1, further comprisingprinting a label with information regarding waste within the container.11. A method of sorting medical waste for disposal, the methodcomprising: identifying a plurality of containers in a sorting stationand determining a waste category associated with each container;identifying an item of waste to be disposed of and assigning the item toa waste category.
 12. The method of claim 11, further comprisingfacilitating disposal of the item in a container associated with theassigned category.
 13. The method of claim 11, wherein identifying aplurality of containers comprises reading an identification key on eachcontainer.
 14. The method of claim 11, wherein the waste category of acontainer is independent of a physical position of the container in asorting station.
 15. The method of claim 11, wherein identifying aplurality of containers comprises determining a color of each container.16. The method of claim 11, further comprising determining that thewaste item is a composite waste item made up of a plurality of separablewaste items.
 17. The method of claim 16, further comprising assigningthe plurality of separable waste items to different waste categories.18. The method of claim 17, further comprising facilitating disposal ofthe plurality of waste items in separate containers.
 19. A method ofsorting medical waste, the method comprising: identifying a plurality ofcontainers in a sorting station and determining at least one wastecategory associated with each container, wherein the waste categoriesare ranked from least to most hazardous; identifying an item of waste tobe disposed of; and assigning the item to a first waste category;determining whether a container associated with the first waste categoryis present in the sorting station; if a container associated with thefirst waste category is not present, re-assigning the waste item to asecond waste category that is ranked more hazardous than the first wastecategory.
 20. The method of claim 19, further comprising storing aninformation log indicating the first waste category and the second wastecategory.
 21. The method of claim 19, further comprising prompting auser to insert a container associated with the first category into thestation.
 22. A method of sorting medical waste items for disposal, themethod comprising: identifying a plurality of containers in a sortingstation and determining a waste category associated with each container,wherein the waste categories are ranked from least to most hazardous;identifying an item of waste to be disposed of; and assigning the itemto a first waste category; determining whether a container associatedwith the first waste category is present in the sorting station; if acontainer associated with the first waste category is not present,directing a user to another sorting station having a containerassociated with the first waste category.
 23. The method of claim 22,further comprising prompting a user to insert a container associatedwith the first category into the station.